#!/bin/sh
# Make sure this shim uses the same Ruby interpreter that is used by Homebrew.
unset RUBYLIB
unset RUBYOPT
if [ -z "$HOMEBREW_RUBY_PATH" ]
then
  echo "${0##*/}: The build tool has reset ENV; --env=std required." >&2
  exit 1
fi
exec "$HOMEBREW_RUBY_PATH" -x "$0" "$@"
#!/usr/bin/env ruby -W0

require "pathname"
require "set"

def mac?
  RUBY_PLATFORM[/darwin/]
end

def linux?
  RUBY_PLATFORM[/linux/]
end

class Cmd
  attr_reader :config, :prefix, :cellar, :opt, :tmpdir, :sysroot, :deps
  attr_reader :archflags, :optflags, :keg_regex, :formula_prefix

  def initialize(arg0, args)
    @arg0 = arg0
    @args = args.freeze
    @config = ENV.fetch("HOMEBREW_CCCFG") { "" }
    @prefix = ENV["HOMEBREW_PREFIX"]
    @cellar = ENV["HOMEBREW_CELLAR"]
    @opt = ENV["HOMEBREW_OPT"]
    @tmpdir = ENV["HOMEBREW_TEMP"]
    @sysroot = ENV["HOMEBREW_SDKROOT"]
    @archflags = ENV.fetch("HOMEBREW_ARCHFLAGS") { "" }.split(" ")
    @optflags = ENV.fetch("HOMEBREW_OPTFLAGS") { "" }.split(" ")
    @deps = Set.new(ENV.fetch("HOMEBREW_DEPENDENCIES") { "" }.split(","))
    @formula_prefix = ENV["HOMEBREW_FORMULA_PREFIX"]
    # matches opt or cellar prefix and formula name
    @keg_regex = %r[(#{Regexp.escape(opt)}|#{Regexp.escape(cellar)})/([\w+-.@]+)]
  end

  def mode
    if @arg0 == "cpp"
      :cpp
    elsif ["ld", "ld.gold", "gold"].include? @arg0
      :ld
    elsif @args.include? "-c"
      if @arg0 =~ /(?:c|g|clang)\+\+/
        :cxx
      else
        :cc
      end
    elsif @args.include?("-xc++-header") || @args.each_cons(2).include?(["-x", "c++-header"])
      :cxx
    elsif @args.include? "-E"
      :ccE
    else
      if @arg0 =~ /(?:c|g|clang)\+\+/
        :cxxld
      else
        :ccld
      end
    end
  end

  def tool
    @tool ||= case @arg0
    when "ld" then "ld"
    when "gold", "ld.gold" then "ld.gold"
    when "cpp" then "cpp"
    when /llvm_(clang(\+\+)?)/
     "#{ENV["HOMEBREW_PREFIX"]}/opt/llvm/bin/#{$1}"
    when /\w\+\+(-\d(\.\d)?)?$/
      case ENV["HOMEBREW_CC"]
      when /clang/
        "clang++"
      when /llvm-gcc/
        "llvm-g++-4.2"
      when /(g)?cc(-\d(\.\d)?)?$/
        "g++" + $2.to_s
      end
    else
      # Note that this is a universal fallback, so that we'll always invoke
      # HOMEBREW_CC regardless of what name under which the tool was invoked.
      if ENV["HOMEBREW_CC"] == "llvm_clang"
        "#{ENV["HOMEBREW_PREFIX"]}/opt/llvm/bin/clang"
      else
        ENV["HOMEBREW_CC"]
      end
    end
  end

  def args
    if @args.length == 1 && @args[0] == "-v"
      # Don't add linker arguments if -v passed as sole option. This stops gcc
      # -v with no other arguments from outputting a linker error. Some
      # software uses gcc -v (wrongly) to sniff the GCC version.
      return @args.dup
    end

    if !refurbish_args? || tool == "ld" || configure?
      args = @args.dup
    else
      args = refurbished_args
    end

    if sysroot
      if tool == "ld"
        args << "-syslibroot" << sysroot
      else
        args << "-isysroot" << sysroot << "--sysroot=#{sysroot}"
      end
    end

    case mode
    when :ccld
      cflags + args + cppflags + ldflags
    when :cxxld
      cxxflags + args + cppflags + ldflags
    when :cc
      cflags + args + cppflags
    when :cxx
      cxxflags + args + cppflags
    when :ccE
      args + cppflags
    when :cpp
      args + cppflags
    when :ld
      ldflags + args
    end
  end

  def refurbished_args
    @lset = Set.new(library_paths + system_library_paths)
    @iset = Set.new(isystem_paths + include_paths)

    args = []
    enum = @args.each

    loop do
      case arg = enum.next
      when "-arch"
        if permit_arch_flags?
          args << arg << enum.next
        else
          enum.next
        end
      when "-m32", "-m64"
        args << arg if permit_arch_flags?
      when /^-Xarch_/
        refurbished = refurbish_arg(enum.next, enum)
        unless refurbished.empty?
          args << arg
          args += refurbished
        end
      else
        args += refurbish_arg(arg, enum)
      end
    end

    args
  end

  def refurbish_arg(arg, enum)
    args = []

    case arg
    when /^-g\d?$/, /^-gstabs\d+/, "-gstabs+", /^-ggdb\d?/,
      /^-march=.+/, /^-mtune=.+/, /^-mcpu=.+/,
      /^-O[0-9zs]?$/, "-fast", "-no-cpp-precomp",
      "-pedantic", "-pedantic-errors", "-Wno-long-double",
      "-Wno-unused-but-set-variable"
    when "-fopenmp", "-lgomp", "-mno-fused-madd", "-fforce-addr", "-fno-defer-pop",
      "-mno-dynamic-no-pic", "-fearly-inlining", /^-f(?:no-)?inline-functions-called-once/,
      /^-finline-limit/, /^-f(?:no-)?check-new/, "-fno-delete-null-pointer-checks",
      "-fcaller-saves", "-fthread-jumps", "-fno-reorder-blocks", "-fcse-skip-blocks",
      "-frerun-cse-after-loop", "-frerun-loop-opt", "-fcse-follow-jumps",
      "-fno-regmove", "-fno-for-scope", "-fno-tree-pre", "-fno-tree-dominator-opts",
      "-fuse-linker-plugin", "-frounding-math"
      # clang doesn't support these flags
      args << arg unless tool =~ /^clang/
    when "--fast-math"
      arg = "-ffast-math" if tool =~ /^clang/
      args << arg
    when "-Wno-deprecated-register"
      # older gccs don't support these flags
      args << arg unless tool =~ /^g..-4.[02]/
    when /^-Wl,-z,defs/
      # -Wl,-undefined,error is already the default
    when /^-W[alp],/, /^-Wno-/
      args << arg
    when /^-W.*/
      # prune warnings
    when "-macosx_version_min", "-dylib_install_name"
      args << "-Wl,#{arg},#{enum.next}"
    when "-multiply_definedsuppress"
      args << "-Wl,-multiply_defined,suppress"
    when "-undefineddynamic_lookup"
      args << "-Wl,-undefined,dynamic_lookup"
    when /^-isysroot/, /^--sysroot/
      if mac?
        sdk = enum.next
        # We set the sysroot for macOS SDKs
        args << "-isysroot" << sdk unless sdk.downcase.include? "osx"
      else
        args << arg << enum.next
      end
    when "-dylib"
      args << "-Wl,#{arg}"
    when /^-I(.+)?/
      # Support both "-Ifoo" (one argument) and "-I foo" (two arguments)
      val  = chuzzle($1) || enum.next
      path = canonical_path(val)
      args << "-I#{val}" if keep?(path) && @iset.add?(path)
    when /^-L(.+)?/
      val  = chuzzle($1) || enum.next
      path = canonical_path(val)
      args << "-L#{val}" if keep?(path) && @lset.add?(path)
    else
      args << arg
    end

    args
  end

  def keep?(path)
    # Allow references to self
    if formula_prefix && path.start_with?("#{formula_prefix}/")
      true
    # first two paths: reject references to Cellar or opt paths
    # for unspecified dependencies
    elsif path.start_with?(cellar) || path.start_with?(opt)
      dep = path[keg_regex, 2]
      dep && @deps.include?(dep)
    elsif path.start_with?(prefix, tmpdir)
      true
    elsif path.start_with?("/opt/local", "/opt/boxen/homebrew", "/opt/X11", "/sw", "/usr/X11")
      # ignore MacPorts, Boxen's Homebrew, X11, fink
      false
    elsif mac?
      true
    else
      false
    end
  end

  def cflags
    args = []

    return args unless refurbish_args? || configure?

    args << "-pipe"
    args << "-w" unless configure?
    args << "-#{ENV["HOMEBREW_OPTIMIZATION_LEVEL"]}"
    args.concat(optflags)
    args.concat(archflags)
    args << "-std=#{@arg0}" if @arg0 =~ /c[89]9/
    args
  end

  def cxxflags
    args = cflags
    args << "-std=c++11" if cxx11?
    args << "-stdlib=libc++" if libcxx?
    args << "-stdlib=libstdc++" if libstdcxx?
    args
  end

  def cppflags
    path_flags("-isystem", isystem_paths) + path_flags("-I", include_paths)
  end

  def ldflags_mac(args)
    case mode
    when :ld
      args << "-headerpad_max_install_names"
      args << "-no_weak_imports" if no_weak_imports?
    when :ccld, :cxxld
      args << "-Wl,-headerpad_max_install_names"
      args << "-Wl,-no_weak_imports" if no_weak_imports?
    end
    args
  end

  def ldflags_linux(args)
    unless mode == :ld
      wl = "-Wl,"
      args << "-B#{@opt}/glibc/lib"
    end
    args += rpath_flags("#{wl}-rpath=", rpath_paths)
    args += ["#{wl}--dynamic-linker=#{dynamic_linker_path}"] if dynamic_linker_path
    args
  end

  def ldflags
    args = path_flags("-L", library_paths)
    if mac?
      ldflags_mac(args)
    elsif linux?
      ldflags_linux(args)
    else
      args
    end
  end

  def isystem_paths
    path_split("HOMEBREW_ISYSTEM_PATHS")
  end

  def include_paths
    path_split("HOMEBREW_INCLUDE_PATHS")
  end

  def library_paths
    path_split("HOMEBREW_LIBRARY_PATHS")
  end

  def rpath_paths
    path_split("HOMEBREW_RPATH_PATHS")
  end

  def dynamic_linker_path
    chuzzle(ENV["HOMEBREW_DYNAMIC_LINKER"])
  end

  def system_library_paths
    paths = ["#{sysroot}/usr/lib"]
    paths << "/usr/local/lib" unless sysroot || ENV["SDKROOT"]
    paths
  end

  def configure?
    # configure scripts generated with autoconf 2.61 or later export as_nl
    ENV.key? "as_nl"
  end

  def refurbish_args?
    config.include?("O")
  end

  def cxx11?
    config.include?("x")
  end

  def libcxx?
    config.include?("g")
  end

  def libstdcxx?
    config.include?("h")
  end

  def permit_arch_flags?
    config.include?("K")
  end

  def no_weak_imports?
    config.include?("w")
  end

  def canonical_path(path)
    path = Pathname.new(path)
    path = path.realpath if path.exist?
    path.to_s
  end

  def path_flags(prefix, paths)
    paths = paths.uniq.select { |path| File.directory?(path) }
    paths.map! { |path| prefix + path }
  end

  # Unlike path_flags, do not prune non-existant directories.
  # formula.lib for example does not yet exist, but should not be pruned.
  def rpath_flags(prefix, paths)
    paths.uniq.map { |path| prefix + path }
  end

  def path_split(key)
    ENV.fetch(key) { "" }.split(File::PATH_SEPARATOR)
  end

  def chuzzle(val)
    return val if val.nil?
    val = val.chomp
    return val unless val.empty?
  end
end

def log(basename, argv, tool, args)
  return unless ENV.key?("HOMEBREW_CC_LOG_PATH")

  adds = args - argv
  dels = argv - args

  s = ""
  s << "#{basename} called with: #{argv.join(" ")}\n"
  s << "superenv removed:  #{dels.join(" ")}\n" unless dels.empty?
  s << "superenv added:    #{adds.join(" ")}\n" unless adds.empty?
  s << "superenv executed: #{tool} #{args.join(" ")}\n\n"
  File.open("#{ENV["HOMEBREW_CC_LOG_PATH"]}.cc", "a+") { |f| f.write(s) }
end

def remove_superbin_from_path(paths)
  superbin = Pathname.new(__FILE__).dirname.realpath
  paths.reject do |x|
    path = Pathname.new(x)
    path.directory? && path.realpath == superbin
  end
end

if __FILE__ == $PROGRAM_NAME
  ##################################################################### sanity

  if (cc = ENV["HOMEBREW_CC"]).nil? || cc.empty? || cc == "cc"
    # those values are not allowed
    ENV["HOMEBREW_CC"] = "clang"
  end

  ####################################################################### main

  dirname, basename = File.split($0)

  cmd = Cmd.new(basename, ARGV)
  tool = cmd.tool
  args = cmd.args

  log(basename, ARGV, tool, args)

  args << { :close_others => false }
  if mac?
    exec "#{dirname}/xcrun", tool, *args
  else
    paths = ENV["PATH"].split(":")
    paths = remove_superbin_from_path(paths)
    paths.unshift "#{ENV["HOMEBREW_PREFIX"]}/bin"
    ENV["PATH"] = paths.join(":")
    exec tool, *args
  end
end
